Rheostat



Mar. 27, 1923. 1,449,557

L. A. SEISS I RHEOSTAT Filed May 6, 1922 lllililllllliilllllllllllWUIMUHHNHIIIMIIIIMIMBJH"1% Patented Mar. 2'7, 1923.

LEONARD A. SEISS, OF TOLEDO; OHIO.

RHEOSTAT.

Application filed Kay 6, 1922. Serial No. 559,048.

T 0 all whom it may concern Be it known that I, LEONARD A. Sinss, acitizen of the United States, and a resident of Toledo, in the county ofLucas and State of Ohio, have made an invention appertaining to aRheostat; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and to the characters ofreference marked thereon which form a part of this specification.

My invention has for its object to provide a rheostat that may bereadily assembled. It particularly has for its object to provide asupporting means for theparts of the rheostat thatmay be efficientlymade and yet when assembled with the rheostat parts will produce anexceedingly eflicient rheostat.

The invention may be contained in structures that differ in theirdetails. To illustrate a practical application of the invention I haveselected one of such structures as an example of structures containingthe invention and shall describe it hereinafter. structure selected isillustrated in the accompanying drawings.

Figure 1 of the drawings is a top view of the rheostat. Fig. 2 is abottom view of the rheostat. Fig. 3 is a side view of the rheostat. Fig.4 is a sectional view taken on the line 44 indicated in Fig. 2. Fig. 5is an enlarged sectional view taken on the line 55 indicated in Fig. 2.Fig. 6 illustrates the top view of a stamping from insulating sheetmaterial forming a part of the base or supporting member of therheostat.

l is a rotatable handle having an indicating pointer 2 that may be movedover'a suitable dial formed on the top of the rheostat to indicate theamount of resistance introduced in a circuit by manipulation of therheostat in the manner well known in the art. The handle 1 and thepointer 2 are coir nected to a shaft or rod 3 to which is also connecteda spring contact 4. Rotation of the handle 1 causes rotation of the rod3. the pointer 2 and the spring contact The rod 3 is secured in asupporting base formed of two discs 5 and 6 of sheet insulatingmaterial, such as insulating fiber board. The lower disc 6 is providedwith a circular slot 7 that extends substantially concentric with theperiphery of the disc. the

The

ends of the slot terminating at a small angular distance from eachother. The slot 7 is so formed that the upper edges 8 are located moreremote from each other than the lower edges 9. whereby the surfacesbetween the edges 8 and 9 are inclined to the top and bottom surfaces ofthe disc 6, the edges 9 being formed by surfaces that form a lesserangle than the angle formed by the surfaces that join along the edges 8.A collar 10 of insulating material and whichis substantially cylindricalin form is located in the slot 7, its ends terminating near or at theends of the slot 7. The insulating collar or substantially cylindricalmember 10 is provided with a resistance wire 11 that is wound on itssurface, the windings being located in suflicient proximity to eachother to permit a continuous contact between the wire and the springcontact 4 when the handle 1, is rotated and so that the spring contactlwill readily slide over the windings of the wire.

The collar or cylindrical insulating member 10, together with the wirewound thereon, is forced into the slot-7. The bevelled sides of the slot7, and particularly the corners formed by the edges 9, quite tightlyclamped against the windings of the wire and thus operate to hold thewire and the cylindrical member 10 in position in the slot 7. The disc 5is located above the disc 6 and thus the slot 7 forms a channel in thebase in which the resistance wire and its insulating core 10 aresecured. The two discs are secured together by meansof the ring 12 ofsheet material which is provided with a flange 13 extendingsubstantially at right angles to the outer surface of the ring 12. Thering 12 is inserted over the edges of the discs 5 and 6 and then theedge portion 14 of the ring 12 is spun down over the edge of the disc 6,which clamps the narrow peripheral portion 15 of the disc 6 against theresistance wire located on the core 10. This crowds the edges 9 againstthe wire throughout the length of the slot 7 and thus the resistanceelement of the rheostat is firmly clamped in position. It may also beheld in position by means of lugs 16 formed on the ends of thesubstantially cylindrical collar 10. The lugs 16 fit under sleeves 17located on the screws 18 that extend downward through the upper disc 5.Clamping screws 18 may also be threaded into the lower ends of thesleeves 17 and form a means for connecting an external circuit with therheostat. The thus form binding posts of the rheostat. ne of the sleeves17 is connected with the shaft or rod 3 and electrically connected withthe contact 4, while one end oft-he resistance wire 11 is connected withthe other sleeve 17 or the binding post that is formed by the sleeve 17and the screws that are threaded therein. By this arrangement thecircuit passes from one binding post through the resistance Wire to thecontact 4 and'thence to the other binding post, in the manner wellknown.

I claim:

1. In a rheostat, a resistance element arranged in substantiallycylindrical form, a base formed of insulating material and having a slotlocated in proximity to the periphery and forming a flexible clampingportion in the peripheral portion of the base, and a ring for clampingand holding the edges of the channel against opposite sides of theresistance element.

2. In a rheostat, a resistance element arranged in substantiallycylindrical form. a base formed of insulating material and having a slotlocated in proximityto the periphery and forming a flexible clampingportion in the peripheral portion of the base, and a rin located aroundthe edge of the base and aving an edge spun down against the flexibleportion.

3. In a rheostat, a resistance element arranged in substantiallycylindrical form, a base formed of a pair of discs, one of the discshaving a slot in which an edge portion of the resistance element issecured by the clamping of the sides of the slot.

t. In a rheostat, a resistance element arranged in substantiallycylindrical form, a base formed of a pair of discs, one of the discshaving a slot in which an edge por tion of the resistance element islocated, and means for clamping and holding the edges of the slotagainst opposite sides of the resistance element. v

In a rheostat, a resistance element arrangedin substantially cylindricalform, a base formed of a pair of discs, one of the discs having a slotlocated in proximity to the periphery forming a flexible clampingportion, and means for clamping and holdsides of the resistance element.

6. In a rheostat, a' resistance element arranged in substantiallycylindrical form, a base formed of a pair of discs, one of the discshaving a slot located in proximity to the periphery forming a flexibleclamping portion, and a ring for clamping and holding the edges of theslot against opposite sides of the resistance element.

In testimony whereof, I have hereunto signed my name to thisspecification.

LEONARD SEISS.

ing the edges of the slot against opposite

